Mitt Romney and Paul Ryan both tout their faith as the foundation of their politics and espouse puritan notions of wealth through righteousness. Photograph: Win Mcnamee/Getty

God loves Republicans, as they'll be the first to tell you. A Florida pastor is taking credit for praying Hurricane Isaac away from the Republican national convention. Instead, the wind and water went off to smite the wicked (and largely Democratic) city of New Orleans.

The GOP faithful see the US as a chosen nation, blessed with prosperity through a special relationship with the almighty. At the convention in Tampa, speaker after speaker invoked the deity almost as often as they talked about money. There's a long history of this, of course, going back to the Puritans. John Robinson, pastor to the Mayflower pilgrims, said: "The blessings of the Lord make rich, and as riches are themselves God's blessings, so we do desire them, for the comfortable course of our natural and civil states."

Mitt Romney and his running mate Paul Ryan both tout their faith as the foundation of their politics and, though Romney's a Mormon and Ryan a Roman Catholic, both espouse puritan notions of wealth through righteousness, never mind what Jesus said about how it's "easier for a camel to go through the eye of a needle than for a rich man to enter into the kingdom of God". Perhaps when he goes to meet his maker, Romney will just whip out his platinum card and buy a very large needle.

Ryan, whose path to prosperity budget blueprint has made him a star among ultra-conservatives, largely ignores his church's teachings on social justice. His plan would slash $6tn from everything except the Pentagon war machine and America's fat and happy plutocracy. More than 60% of Ryan's cuts would hit programmes for the poor, the old, the sick and the unemployed. America's Catholic bishops, not exactly commie pinkos, sent a letter to Congress calling Ryan's attack on the poor "unjustified and wrong". Perhaps Ryan didn't pay attention in Sunday school; perhaps he hid The Fountainhead inside his New Testament.

Not everyone would lose out in Ryan's scheme: the richest would get a tax break. Romney – the standard-bearer for the 1% – would pay less than 1%. Praise the Lord!

Once the party of civil rights, progressive gender politics and environmental stewardship, today's Republicans are obsessed with cutting taxes and imposing their version of sexual morality on a depraved "reality" TV-watching populace. You'd think they were disciples of Michael Wigglesworth, the 17th-century Massachusetts preacher whose pronouncements (as Huck Finn said of Pilgrim's Progress) were "interesting but tough".

Like Romney, Wigglesworth was a Harvard graduate; like both Romney and Ryan, he had an unflinching, un-nuanced sense of sin, as expounded in his 1662 best-selling poem The Day of Doom. God appears at the Last Judgment and brusquely separates humanity into sheep (good) and goats (bad). "Amorites and sodomites", drinkers, people who lived virtuously though without faith, people who couldn't understand the Bible, people who never heard of the Bible, people who didn't get a chance to repent, people who counted on God's last-minute mercy, uppity women and "reprobate infants" – unbaptised babies – all headed for eternal torment.

The babies put up a fight, arguing they shouldn't be blamed (they're babies, after all) but God says sorry, rules are rules. The best he can do is give them "the easiest room in hell".

Ryan is not, as far as we know, a reader of Wigglesworth. He's a long-time disciple of Ayn Rand, though lately he's been trying to disassociate himself from her, what with her being a pro-choice atheist (he's just now figuring that out?). He hasn't weighed in on the way her fiction romanticises rape. Perhaps he should, given his association with the notorious Missouri Republican Todd Akin – the guy who opined that victims of "legitimate rape" didn't get pregnant. This past congressional session, Ryan joined Akin and other Republicans in trying to redefine rape and push a "personhood" bill, giving zygotes the same 14th amendment rights as citizens.

Lately Ryan's been citing Thomas Aquinas. He should take another look at Summa Theologica. In part II, St Thomas argues: "Whatever a man has in superabundance is owed, of natural right, to the poor for their sustenance. So Ambrosius says, and it is also to be found in the Decretum Gratiani: 'The bread which you withhold belongs to the hungry: the clothing you shut away, to the naked: and the money you bury in the earth is the redemption and freedom of the penniless.'"

The call to share seems pretty clear, but Ryan (and Romney) cling to the conviction that America should reward those to whom much has been given, and take from those who have next to nothing. Romney tithes (his wife has been quoted as saying that when they give their cheque to the church, "I actually cry!"), but he won't release his tax returns and refuses to acknowledge that a little charity sprinkled on top of social Darwinist economics still tastes bitter to most Americans. It's all about profit. William Perkins, a Cambridge divine very influential in 17th-century New England, endorsed a society of haves and have-nots: "If we happen to have inherited much property, we are to enjoy these in good conscience as blessings and gifts of God."

In the puritan tradition, money was a sign of God's favour, even of virtue. Three centuries later, Americans still think rich people (even Donald Trump) must be doing something right. Jesus's "feed my sheep" stuff? That's socialism. If those sheep were real Americans, they'd get up off their woolly backsides and get a job. Maybe they're just goats in disguise, the undeserving poor. As Wigglesworth put it:

You sinners are, and such a share As sinners may expect,Such you shall have; for I do saveNone but my own elect.

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